I can't say enough about this organization. As watchdogs of the Hudson River, they have had a huge impact on improving the health of the Hudson over the last 50 years. Their greatest strength is policy in NY state. They are taking great steps to put a ban on fracking and shut down Indian Point (a nuclear site which is unsafe for the people of NYC and the river). Last year they successfully made the NY Sewage Pollution Right to Know Act law.
They are always out on the boat taking water quality tests and helping swimmers know when and where it's safe to swim. I have volunteered with them on river clean ups, distributed information at events, sponsored them for grants and attended educational events they promote. The dream of a clean Hudson is coming true.